This undated photo provided by the Tennessee Department of Correction shows Billy Ray Irick, currently on death row at Riverbend Maximum Security Institution in Nashville, Tenn. Irick was convicted for raping and killing a 7-year-old girl in 1985, and is scheduled to be executed Thursday, Aug. 9, 2018. (Tennessee Department of Correction via AP)

FILE - In this Aug. 16, 2010 file photo, Billy Ray Irick, on death row for raping and killing a 7-year-old girl in 1985, appears in a Knox County criminal courtroom in Knoxville, Tenn., arguing that he's too mentally ill to be executed by the state. The Tennessee Supreme Court has refused to stay Thursday's Aug. 9, 2018, scheduled execution of the convicted child killer while the state's new lethal injection protocol continues to be challenged on appeal. The order brings Tennessee within days of killing Irick with a three-drug cocktail, barring some last-minute change. (Michael Patrick/The Knoxville News Sentinel via AP, File)

CORRECTS SPELLING OF PHOTOGRAPHER'S NAME TO MAYS INSTEAD OF MAYES - Kathy Jeffers, second from left, mother of victim Paula Dyer, arrives with relatives and friends for the execution of Billy Ray Irick at Riverbend Maximum Security Institution in Nashville on Thursday, Aug. 9, 2018. Irick is scheduled to receive a three-drug injection Thursday evening at the maximum-security prison in Nashville. He was convicted in 1986 in the death of Dyer, a Knoxville girl he was babysitting. (Shelley Mays/The Tennessean via AP)